Friday, June 26, 2015

There were pennaceous-feathered, long-bony-tailed primitive birds.
The most basal were flying (eg. scansoriopterygids, tetrapterygids).
Some later ones became secondarily flightless (eg. oviraptors, eudromaeosaurids etc).

These primitive birds have a great deal in common with pterosaurs. They evolved from pterosaurs.
These primitive birds have almost nothing in common with dinosaurs.

Considerable debate surrounds the numerous
avian-like traits in core maniraptorans (oviraptorosaurs,
troodontids, and dromaeosaurs), especially in the
Chinese Early Cretaceous oviraptorosaur Caudipteryx,
which preserves modern avian pennaceous primary remiges
attached to the manus, as is the case in modern birds.Was Caudipteryx derived from earth-bound theropod dinosaurs,which is the predominant view among palaeontologists,or was it secondarily flightless, with volant avians
or theropods as ancestors (the neoflightless hypothesis),
which is another popular, but minority view. The discoveryhere of an aerodynamic propatagium in several specimensprovides new evidence that Caudipteryx (and hence oviraptorosaurs)represent secondarily derived flightlessground dwellers, whether of theropod or avian affinity, and
that their presence and radiation during the Cretaceous may
have been a factor in the apparent scarcity of many other
large flightless birds during that period.

Friday, June 5, 2015

The following study shows that there were 51 synapomorphies (unique defining characteristics) for Paraves (primitive birds). This means that of the 374 characteristics that were evaluated, 51 of them were different than the claimed dinosaur ancestor. This is more than 1 in 8. This means that primitive birds are not similar to dinosaurs, which is a point that I have being making for a very long time. It is good to see a cladistic analysis confirm this point. Note that this number would be very much larger if the oviraptors etc were taken as secondarily flightless.2011 study (Xu et al):http://www.nature.com/nature/journal/v475/n7357/full/nature10288.htmlhttp://www.ivpp.cas.cn/qt/papers/201403/P020140314389417822583.pdfAn Archaeopteryx-like theropod [Xiaotingia] from China and the origin of Avialae

Here we report a new Archaeopteryx-like theropod from China. This find further demonstrates thatmany features formerly regarded as being diagnostic of Avialae, including long and robust forelimbs, actually characterize the more inclusive group Paraves (composed of the avialans and the deinonychosaurs).

Note

This site presents the idea that pterosaurs (rather than dinosaurs) developed into birds. This is not an "evolutionism" vs. "creationism" issue.An "evolutionist" can say that the pterosaur to bird developments are due to neo-Darwinian means (random mutation and natural selection).On the other hand, a "creationist" can say that those developments are the acts of a higher intelligence.This site does not take a position on the "evolutionism" vs. "creationism" question.

Philosophy

Like most people, I have philosophical ideas that go beyond the nuts and bolts of the scientific analysis of the origin and development of birds.There are larger questions that philosophers have grappled with since the most ancient times. If anyone is interested in my take on those more philosophical ideas, click here.But please realize that all the ideas of this site are pure materialist, scientific ideas supported by physical evidence and scientific studies.

The 19th-century German philosopher Arthur Schopenhauer astutely summarized the three stages through which all truth passes: first, it is ridiculed; second, it is violently opposed;

and third, it is accepted as being self-evident.

"In the choice between changing one's mind and proving there's no need to do so, most people get busy on the proof."~John Kenneth Galbraith

Keywords

origin of birds, pterosaur is the ancestor of modern birds, birds did not evolve from dinosaurs, cladistics, stratocladistics, Cretaceous, Mesozoic, fossil record, BAD, BAND, birds are not dinosaurs, flightless birds, aves